J Korean Med Sci.  2005 Jun;20(3):461-467. 10.3346/jkms.2005.20.3.461.

Clinical Effectiveness of Urinary Human Chorionic Gonadotropin Related Protein (hCGRP) Quantification for Diagnosis of Ectopic Pregnancy

• Lee JK
• Oh MJ
• Shin JS
• Lee KJ
• Nam JH
• Cha JH
• Chang JD
• Cho DH
• Kang IS
• Lee PI

• KMID: 1778507
• DOI: http://doi.org/10.3346/jkms.2005.20.3.461

Abstract

We detected pregnancy related new molecule, human chorionic gonadotropin related protein (hCGRP) in the urine of a pregnant women by using a monoclonal antibody against the human chorionic gonadotropin (hCG). This study examined the effectiveness of urinary hCGRP quantification in diagnosing ectopic pregnancy. This study included 40 normal pregnant women and 25 patients with ectopic pregnancy. Patients' serum and urinary intact whole hCG (i-hCG) and hCGRP concentrations were measured using sandwich ELISA and the ratio of hCGRP to i-hCG was calculated. Statistical analysis was performed using statistical package for social sciences (SPSS) 10.0. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the cut-off value to discriminate ectopic pregnancies from normal intrauterine pregnancies. Urinary hCGRP and hCGRP/i-hCG ratio in ectopic pregnancy group (14 +/- 6.6 ng/mL, 4.6 +/- 1.9%, respectively) were significantly lower than those of normal pregnancy group (149 +/- 10.2 ng/mL, 29.7 +/- 1.9%, respectively; p<0.001). Based on ROC curve analysis, a cut-off point of urinary hCGRP/i-hCG ratio <16.2% discriminated between ectopic pregnancy and normal pregnancy with a sensitivity, specificity, positive predictive value and negative predictive value of 92.0%, 90.0%, 32.6%, and 99.5%, respectively. Urinary hCGRP/i-hCG ratio measurement may be effective in diagnosing ectopic pregnancy.

Keyword

Pregnancy, Ectopic; Early Diagnosis; Chorionic Gonadotropin; Human Chorionic Gonadotropin Related Protein

MeSH Terms

Adult
Antibodies, Monoclonal/immunology
Chorionic Gonadotropin/*diagnostic use/immunology/urine
Enzyme-Linked Immunosorbent Assay/methods
Female
Humans
Pregnancy
Pregnancy, Ectopic/*diagnosis/urine
Sensitivity and Specificity

Figure

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  Fig. 1 Specific reactivity of two anti-hCG monoclonal antibody pairs (HSα6301/HSM6238, HSM6042/HSM6043) to intact hCG.

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  Fig. 2 Distribution of i-hCG and hCGRP concentration in intrauterine pregnancy and ectopic pregnancy. (A) Urine of intrauterine pregnancy, (B) Urine of ectopic pregnancy, (C) Serum of intrauterine pregnancy, (D) Serum of ectopic pregnancy.

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  Fig. 3 Mean hCGRP/i-hCG ratios and 95% confidence intervals in intrauterine pregnancy and ectopic pregnancy group. (A) Urine samples, (B) Serum samples. IUP, intrauterine pregnancy; EP, ectopic pregnancy.

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  Fig. 4 Receiver operating characteristic (ROC) curve plotting sensitivity and false positive rate and the optimal discriminatory ihCG/hCGRP ratio cut-off point in serum (filled circle) and urine (filled square). ihCG, intact human chorionic gonadotropin; hCGRP, human chorionic gonadotropin related protein.

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